FIG. 1 illustrates a conventional wireless communication system 100 including wireless devices 102, 104. The wireless device 102 includes a DC power source 106 that provides power to a transmit processor 108, a modulator 110, and a power amplifier 112. The wireless device 102 further includes (optional) regulators 114, 116, 118 that respectively provide a correct voltage and/or current regulation to the transmit processor 108, the modulator 110, and the power amplifier 112. In operation, a transmit frequency (TX Fc, Fc(s)) of the transmit processor 108 is typically set to a specific frequency associated a wireless communication standard—e.g., GSM (global system for mobile communications), wireless LAN (local area network), Bluetooth, and the like. For example, the modulator 110 can comprise a voltage controlled oscillator and phase lock loop to select a given transmit frequency from a range of possible transmit frequencies. The power amplifier 112 amplifies a power of a modulated signal output from the modulator 110, and the output of the power amplifier 112 (referred to in the following Figs. as “TX Signal Power(s))” is transmitted through a transmit antenna 120 into free space. A receiver 122 of the wireless device 104 receives the radiated signal through a receive antenna 124 and processes the radiated signal, thus allowing wireless communication of information between the wireless device 102 and the wireless device 104.
In general, because wireless devices are not connected through a physical wire, signals that are transmitted from a wireless device are typically attenuated (reduced) and/or distorted due to travel in free space. Therefore, as a distance DL(s) (ranging from, e.g., 0 miles to millions of miles) increases between the wireless device 102 and the wireless device 104, an amount of attenuation and/or distortion of signals transmitted from the wireless device 102 to the wireless device 104 also increases. For example, a GSM cellular phone can transmit a signal having a power that averages 1-2 Watts, however, a GSM receiver typically receives a signal having a power as small as 60×10-12 Watts—most of the signal power is lost in free space. Attenuation and/or distortion of a signal can cause an amplitude of a signal to be too low or too distorted for correction by the wireless device 104.